* Third-quarter revenue falls 3 pct to $3.45 bln
* Third-quarter EBTIDA up 3 pct at $1.14 bln
* Expects to sell iron ore from Karnataka via auctions shortly
* Shares fall 2 pct
Jan 31 (Reuters) - London-listed mining and oil company Vedanta Resources Plc's third-quarter revenue fell 3 percent as an unplanned shutdown at its international zinc unit hit production.
Revenue in the quarter ended Dec. 31 fell to $3.45 billion from $3.57 billion a year earlier.
Revenue from zinc international was down 39 percent, with overall revenue from zinc 14 percent lower during the quarter.
Third-quarter production at its zinc international business fell 19 percent due to a maintenance shutdown at Skorpion in Namibia in November and December after a tank failure, the company said. The unit accounts for about 5 percent of total revenue.
Vedanta, controlled by Indian billionaire Anil Agarwal, said group core earnings or earnings before interest, taxes, depreciation, and amortisation (EBITDA) increased 3 percent to $1.14 billion with oil and gas as the key contributor.
Core earnings from the oil and gas unit, which accounts for about 22 percent of revenue, rose 1 percent to $615.7 million.
The miner also said it was ramping up iron-ore production in the southern Indian state of Karnataka to a run-rate of around 0.5 million tonnes per month, and expected to commence sales through auctions shortly.
Vedanta resumed mining iron ore in Karnataka in December following clearance from a court-appointed panel.
The company simplified its byzantine structure last year when it overhauled its web of subsidiaries and created Sesa Sterlite - an umbrella unit that groups most of its assets.
Shares in the company were down 1.8 percent at 822 pence at 0905 GMT on the London Stock Exchange on Friday. They had dropped as much as 4 percent in early trade.